The leagues generally consist of a handful of games per team.
The Utah Jazz Summer League began play in 2015, replacing the Rocky Mountain Revue, an event held from 1984 to 2008 before going on a lengthy hiatus due to declining participation. In 2004, the league held the Las Vegas Summer League for the first time it is by far the largest league, with 32 teams participating as of 2019. The Orlando Pro Summer League was held from 2002 to 2017, operating each year except in 20. Historically, there was not an organized structure, with leagues sometimes overlapping and not officially coordinated.